Imagine throwing a ball into the air and watching it slow down, eventually falling back to the ground. Now, imagine if instead of slowing down, the ball just kept going—faster and faster, forever. Sounds crazy, right? Well, that’s exactly what’s happening to our universe! For over a century, scientists have known that the universe is expanding —but recent discoveries suggest it’s doing so at an accelerating rate . Let’s break down what that really means and why it’s one of the biggest mysteries in physics. What Does It Mean That the Universe is Expanding? When we say the universe is expanding, we’re not talking about galaxies moving through space. Instead, space itself is stretching , carrying galaxies along with it. Think of the universe like a balloon covered in tiny dots. As you blow air into the balloon, the dots (representing galaxies) move away from each other—not because they’re traveling, but because the surface itself is expanding . That’s what’s happening to our cosmos ...